我国是世界上小麦种植面积最大和消费最高的国家之一。小麦为国际主粮之一，也是食品工业的重要原料。作为最重要粮食品种之一的小麦，其价值与用途取决于它的品质。因此，基于信号处理技术，研究客观、便捷的小麦品质测定方法对提高小麦品质、减少产后损失、保证国家粮食安全具有十分重要的意义。本课题拟在研究、分析国内外无损检测技术在农产品品质分析应用现状和研究进展的基础上，研究小麦籽粒声信号的预处理方法。根据声学检测原理，研制出小麦籽粒的声信号采集装置，首先采集小麦籽粒下落碰撞所产生的声音信号，对小麦声信号进行编辑和预处理，实验结合信号处理技术及MATLAB软件，对单粒小麦样品的声信号进行谱估计和小波变换，提取出时域和频域特征参数，为探讨小麦声学特性与其品质指标的关系奠定基础。本论文利用MATLAB软件编写小麦声音信号预处理程序，通过对小麦籽粒声信号进行处理，成功的提取出了有效的时域、频域的多种特征参数，为研究其声学特性与小麦品质内在的关系，做了充分的准备工作。-China is one of the countries in the world which has the largest wheat growing area and highest consumption. Wheat is one kind of the staple food in the world and also an important material for food industry. The value of wheat and its use all depends on is quality, To enhance quality of wheat,readuce post harvest loss and ensure grain security, great efforts should be made to develop rapid, objective, and easy methods for assessing wheat quality using signal processing techniques. This paper do the research of wheat signal preconditioning method and it basis of analysis domestic and foreign non-destructive testing technology.According to acoustic detection theory,an equipment of obtaining wheat sound signals is developed. Collecting the dropping voice signals of different varieties of wheat samples.And then do editing and sound signal preprocessing on wheat through signal processing technology.This paper do some research about spectrum estimate and wavelet transform on single wheat wi